U.S. patent number 6,128,874 [Application Number 09/277,589] was granted by the patent office on 2000-10-10 for fire resistant barrier for dynamic expansion joints.
This patent grant is currently assigned to Construction Specialties, Inc., Unifrax Corporation. Invention is credited to Roger W. Barr, James R. Olson, Lee A. Peekstok.
United States Patent |
6,128,874 |
Olson , et al. |
October 10, 2000 |
Fire resistant barrier for dynamic expansion joints
Abstract
A fire resistant barrier and system for dynamic building
expansion joints comprising a plurality of layers of fire resistant
material comprising: a first mechanical support layer having a
first and second major surface; a second layer having a first and
second major surface, wherein the second layer provides protection
and mechanical support to the fire barrier; and at least one layer
of intumescent sheet material having a first and second major
surface; said at least one layer of intumescent material is
disposed between said first mechanical support layer and said
second layer; and wherein said first mechanical support layer, said
second layer and said at least one layer of intumescent material
are locally bonded together over only a portion of their width
substantially continuously along the length of the layers of said
fire resistant material. The fire barrier is secured to concrete
building members with retainer angle brackets and does not require
the use of conventional caulking materials to effect a tight seal
between the building structure and the fire barrier.
Inventors: |
Olson; James R. (Youngstown,
NY), Barr; Roger W. (Williamsport, PA), Peekstok; Lee
A. (Sanborn, NY) |
Assignee: |
Unifrax Corporation (Niagara
Falls, NY)
Construction Specialties, Inc. (Lebanon, NJ)
|
Family
ID: |
23061534 |
Appl.
No.: |
09/277,589 |
Filed: |
March 26, 1999 |
Current U.S.
Class: |
52/232;
52/396.01; 52/396.04 |
Current CPC
Class: |
E04B
1/948 (20130101) |
Current International
Class: |
E04B
1/94 (20060101); E04B 001/682 () |
Field of
Search: |
;52/232,396.01,396.04 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
UL 2079 Standard for "Tests for Fire Resistance of Building Joint
Systems", Third Edition, Jul. 31, 1998. .
UL 2079 Standard for "Tests for Fire Resistance of Building Joint
Systems", First Edition, Nov. 29, 1994. .
UL Directory, Fire Resistance, vol. 2, 1999 pp. i-ii, 1025, 1031,
1038-1040, 1042-1044, 1135-1136, 1144-1446 & 2307. .
Construction Specialties Expansion Joint Cover Product Catalog,
1998, pp. 6-7. .
Construction Specialties Expansion Joint Cover Product Catalog,
1999, pp. 4-5, 11, 13, 15, 17 & 19. .
MM Systems Seismic and Expansion Control Joint System Product
Catalog, 1998, pp. 20-24. .
Balco Inc. Fire Related Joint Covers Catalog, pp. 3-5. .
Thermal Structures Inc. Fire Barrier Systems for Thermal, Wind Sway
and Seismic Environments, Product Catalog, pp. 2-3. .
Architectural Art Mgf., Inc., Expansion Joint Cover Systems Product
Catalog, Jan. 1999, pp. 20-21..
|
Primary Examiner: Kent; Christopher T.
Attorney, Agent or Firm: Renner, Kenner, Greive, Bobak,
Taylor & Weber
Claims
We claim:
1. A fire resistant barrier for architectural expansion joints
comprising a plurality of fire resistant material layers
comprising:
a first mechanical support layer having a first and second major
surface;
a second layer having a first and second major surface, wherein
said second layer provides protection and mechanical support to
said fire barrier;
at least one layer of intumescent sheet having a first and second
major surface, wherein said at least one layer of intumescent sheet
is disposed between said first mechanical support layer and said
second layer; and
wherein said first mechanical, said second, and said intumescent
sheet layers are locally bonded together only substantially along a
longitudinal center and substantially continuously along the length
of said layers.
2. The fire barrier of claim 1, wherein said second layer comprises
one selected from the group consisting of a polymeric material, a
fiber reinforced polymeric material a metalized fiber reinforced
polymeric material, and a metalized, fiberglass cloth material.
3. The fire barrier of claim 2, wherein said polymeric material is
selected from the group consisting of polypropylene, polyethylene,
polyester, thermoplastic elastomers and thermoplastic rubbers.
4. The fire barrier of claim 3, wherein said polymeric material is
polypropylene.
5. The fire barrier of claim 2, wherein said fibers comprising the
metalized, fiber reinforced polymeric material are selected from
the group consisting of inorganic fibers and polymeric fibers.
6. The fire barrier of claim 5, wherein said polymeric fibers are
aramid fibers.
7. The fire barrier of claim 5, wherein said inorganic fibers are
selected from the group consisting of glass, silica and ceramic
fibers.
8. The fire barrier of claim 2, wherein said metalized, fiber
reinforced polymeric layer is aluminized, glass fiber reinforced
polypropylene material.
9. The fire barrier of claim 2, wherein said metalized, fiber
reinforced polymeric material layer is a structure selected from
the group consisting of a film, foil, sheet, paper, felt, and
blanket.
10. The fire barrier of claim 1, wherein said material comprising
the mechanical support layer is selected from the group consisting
of stainless steel, aluminum, copper and high temperature resistant
woven textiles.
11. The fire barrier of claim 1, wherein said mechanical support
layer is a structure selected from the group consisting of a sheet,
foil, screen, mesh and high temperature resistant woven
textiles.
12. The fire resistant barrier of claim 1, wherein said intumescent
sheet contains intumescent material selected from the group
consisting of unexpanded vermiculite, hydrobiotite, water-swelling
tetrasilicic fluorine mica, expandable graphite and mixtures
thereof.
13. The fire resistant barrier of claim 1, wherein said intumescent
sheet comprises a blend of fibers, wherein said fibers are selected
from the group consisting of refractory ceramic fibers and high
temperature resistant glass fibers; unexpanded vermiculite; and an
organic binder.
14. The fire resistant barrier of claim 13, wherein said
intumescent sheet layer comprises a mat containing about 30 to
about 45 weight percent refractory ceramic fibers, about 45 to
about 60 weight percent unexpanded vermiculite, and about 5 to
about 10 weight percent organic binder.
15. The fire resistant barrier of claim 13, wherein said refractory
ceramic fiber is selected from the group consisting of
alumina-silica, polycrystalline mullite and glass mat
materials.
16. The fire resistant barrier of claim 13, wherein said organic
binder is an acrylic latex binder.
17. The fire resistant barrier of claim 1, wherein said first
mechanical support layer, said second layer and said at least one
intumescent sheet layer are locally bonded together by at least one
of a bonding means selected from the group consisting of tape,
tacks, rivets, stitches, staples and adhesives.
18. The fire resistant barrier of claim 17, wherein said adhesive
is selected from the group consisting of pressure sensitive rubber
adhesive, double adhesive coated films, hot melt rubber adhesive,
hot melt glue and sprayable rubber cement.
19. The fire resistant barrier of claim 1, wherein said barrier is
adapted to be attached to a building structure by retainer angle
brackets.
20. The fire resistant barrier of claim 19, wherein said material
comprising said retainer angle brackets is selected from the group
consisting of galvanized steel, stainless steel and aluminum.
21. A fire resistant barrier system comprising a fire resistant
barrier and at least one radiation heat shield, wherein said fire
resistant barrier comprises a first mechanical support layer having
a first and second major surface; a second layer having a first and
second major surface, wherein said second layer provides protection
and mechanical support to the fire barrier; and at least one layer
of intumescent sheet having a first and second major surface,
wherein said at least one layer of intumescent sheet is disposed
between said first mechanical support layer and said second layer;
wherein said first mechanical support layer, said second layer and
said at least one layer of intumescent sheet are locally bonded
together only substantially along a longitudinal center and
substantially continuously along the length of said layers; and
wherein said at least one radiation heat shield comprises a
plurality of fire resistant material layers comprising at least one
layer of inorganic fibrous mat material having a first and second
major surface encapsulated by two separate layers of metalized,
inorganic fiber reinforced polymeric material.
22. The fire barrier system of claim 21, wherein said second layer
comprises one selected from the group consisting of a polymeric
material, a fiber reinforced polymeric material a metalized, fiber
reinforced polymeric material, and a metalized, fiberglass cloth
material.
23. The fire barrier system of claim 22, wherein said polymeric
material is selected from the group consisting of polypropylene,
polyethylene, polyester, thermoplastic elastomers and thermoplastic
rubbers.
24. The fire barrier system of claim 23, wherein the polymeric
material is polypropylene.
25. The fire barrier system of claim 22, said fibers comprising the
metalized, fiber reinforced polymeric material are selected from
the group consisting of inorganic fibers and polymeric fibers.
26. The fire barrier system of claim 25, wherein said polymeric
fibers are aramid fibers.
27. The fire barrier system of claim 25, wherein said inorganic
fibers are selected from the group consisting of glass, silica and
ceramic fibers.
28. The fire barrier system of claim 22, wherein the metalized,
fiber reinforced polymeric layer is aluminized, glass fiber
reinforced polypropylene material.
29. The fire barrier system of claim 23, wherein said at least one
radiation heat shield is adapted to be installed in the space above
the fire barrier, within a dynamic building expansion joint.
30. The fire barrier system of claim 22, wherein said metalized,
fiber reinforced polymeric material layer is a structure selected
from the group consisting of a film, foil, sheet, paper, felt and
blanket.
31. The fire barrier system of claim 21, wherein said mechanical
support layer is a structure selected from the group consisting of
a sheet, foil, screen, mesh and a high temperature resistant woven
textile.
32. The fire barrier system of claim 21, wherein said material
comprising the mechanical support layer is selected from the group
consisting of stainless steel, aluminum, copper and high
temperature resistant woven textiles.
33. The fire barrier system of claim 21, wherein said intumescent
sheet contains intumescent material selected from the group
consisting of unexpanded vermiculite, hydrobiotite, water-swelling
tetrasilicic fluorine mica, expandable graphite and mixtures
thereof.
34. The fire resistant barrier system of claim 21, wherein said
intumescent sheet layer comprises a blend of fibers, wherein said
fibers are selected from the group consisting of refractory ceramic
fibers and high temperature resistant glass fibers; unexpanded
vermiculite; and an organic binder.
35. The fire resistant barrier system of claim 34, wherein said
intumescent sheet layer comprises a mat containing about 30 to
about 45 weight percent refractory ceramic fibers, about 45 to
about 60 weight percent unexpanded vermiculite, and about 5 to
about 10 weight percent organic binder.
36. The fire resistant barrier system of claim 34, wherein the
refractory ceramic fibers are selected from the group consisting of
alumina-silica fibers, polycrystalline mullite fibers and glass
fibers.
37. The fire resistant barrier system of claim 34, wherein the
organic binder is an acrylate latex binder.
38. The fire resistant barrier system of claim 21, wherein said
first mechanical support layer, said second layer and said at least
one layer of intumescent sheet material are locally bonded together
by at least one of a bonding means selected from the group
consisting of tape, tacks, rivets, stitches, staples and
adhesives.
39. The fire resistant barrier system of claim 38, wherein the
adhesive is selected from the group consisting of pressure
sensitive rubber adhesive, double adhesive coated films, hot melt
rubber adhesive, hot melt glue and sprayable rubber cement.
40. The fire resistant barrier system of claim 21, wherein said
barrier is adapted to be attached to a building structure with
retainer angle brackets.
41. The fire resistant barrier system of claim 40, wherein the
materials comprising said retainer angle brackets are selected from
the group consisting of galvanized steel, stainless steel and
aluminum.
42. The fire resistant barrier system of claim 21, wherein said
system further comprises an expansion joint cover plate providing a
bridge across an expansion joint.
43. A method for installing an architectural expansion joint fire
barrier comprising:
providing a fire resistant barrier comprising a plurality of fire
resistant material layers comprising a first mechanical support
layer material having a first and second major surface; a second
layer having a first and second major surface, wherein said second
layer provides protection and mechanical support for the fire
barrier; and at least one layer of intumescent sheet having a first
and second major surface, wherein said at least one layer of
intumescent is disposed between said first mechanical support layer
and said second layer; wherein said first mechanical, said second,
and said intumescent sheet layers are locally bonded together only
substantially along a longitudinal center and substantially
continuously along the length of said layers; and
affixing said fire barrier to a building structure.
44. The method of claim 43, including affixing to the building
structure, at least one radiation heat shield, and wherein said
radiation heat shield comprises a plurality of fire resistant
materials comprising at least one layer of inorganic fibrous mat
material having a first and second major surface encapsulated by
two separate layers of metalized, inorganic fiber reinforced
polymeric material.
45. The method of claim 43, including installing said at least one
radiation heat shield in the space above said fire barrier, within
a dynamic building expansion joint.
46. The method of claim 43, including affixing said fire resistant
barrier to the building structure with retainer angle brackets.
Description
TECHNICAL FIELD OF THE INVENTION
The present invention is directed to a fire resistant barrier for
use in building structures. The present invention is more
particularly directed to a fire resistant barrier for use in
conjunction with dynamic wall, ceiling and floor expansion joints
to prevent the communication of fire and smoke under the conditions
of a fire in buildings having these types of expansion joints.
BACKGROUND OF THE INVENTION
Architects and engineers must take into account the effects not
only of seismic movement, but also movements caused by building
sway, settlement, thermal expansion and contraction. Architects
know that any building that may be subjected to ground oscillations
must be designed to control and accommodate movement caused by
resonation within the structure while additionally providing for
tower sway, thermal movement and settlement.
To overcome the problems associated with building movement,
architects have
designed buildings with various dynamic expansion joints between
the walls, ceilings and floors to take into account the sway,
ground motion, and settlement associated with buildings. Dynamic
expansion joints are linear openings in a building designed to
allow for building movement.
A disadvantage of the use of expansion joints is that they create a
chimney effect in the building structure, under the conditions of a
fire. Chimney effect refers to the tendency of fire and smoke to
communicate through a vertical passage during a fire. Because fire
is an ever-present danger in association with any building and the
chimney effect at unprotected expansion joints may actually advance
the communication of fire and smoke to other parts of a building,
it is highly desirable to utilize a fire barrier in conjunction
with any expansion joint assembly to provide additional protection
to aid in the prevention of the spreading of any fire.
Fire resistant barriers have been developed that comprise layers of
a suitable fire retardant material reinforced with wire mesh and/or
foils. This metal reinforcement is positioned between the expansion
joint and the fire resistant barrier prior to the application of
the expansion joint assembly. The fire barrier is a highly thermal
resistant material which protects the joint from the associated
chimney effect within the building construction.
Fire barrier devices have also been designed that comprise
flexible, composite barriers including a laminate of intumescent
material and a backing material, such as metal foils or sheets,
paper, plastic, cloth, or a mat of inorganic fibers in a binder.
When exposed to heat or fire, the intumescent materials expand so
as the fill open spaces in the vicinity of the architectural joint
to prevent the passage of smoke, fire, water or gas.
Prior to the development of Underwriters Laboratories' test number
2079 (UL 2079) for the testing of fire resistance of building joint
systems, cycling of the fire barriers before the testing of fire
resistance of a fire barrier in building expansion joint
applications was not required. UL test number 2079 was developed to
include a cycling requirement prior to testing a building joint
expansion system for fire resistance. According to the prior
version of UL 2079, each building expansion joint system was
required to be conditioned by subjecting the joint system to a
minimum of twenty complete movement cycles to provide a condition
representative of expansion joints in building structures, prior to
testing for fire resistance. The conditioning requirement of UL
2079 has recently been changed to require that each building
expansion joint system be conditioned for a minimum of five hundred
complete movement cycles prior to testing for fire resistance.
Other prior art expansion joint treatment systems have included
insulated metal foil (e.g. aluminum) layers such as those disclosed
in the Fire Resistance Directory, published by Underwriter's
Laboratories. Although many prior art fire barriers imply the
capability to move within an expansion joint in response to normal
and seismic building movement, heretofore, no prior art expansion
joint fire barrier system has passed both the cycling requirement
and fire resistance requirement of the new version of UL 2079.
While these fire resistant barrier layers are suitable for
reduction in the chimney effect associated with buildings
containing expansion joints, they clearly can be improved.
LaRoche et al., U.S. Pat. No. 4,977,719, discloses a fire resistant
expansion joint comprising a fire barrier comprised of a flexible
fire resistant inorganic refractory fiber fabric sheet which
supports resilient fire resistant inorganic refractory fibers. The
flexible fire resistant inorganic refractory fiber fabric sheet is
curved across its width to accommodate movement of the spaced
building members.
Wilson et al., U.S. Pat. No. 5,502,937 discloses a fire protective
flexible composite insulating system for either static or dynamic
joints comprising a first layer material having a first and second
major surface, the first layer material including inorganic fibers
and a binder in the form of a flexible mat; a second layer material
adhered to the first major surface of the first layer material, the
second layer material consisting essentially of metal foil, and a
third layer adhered to the second major surface of the first
material, the third layer material including an intumescent fire
retardant composite material. In a preferred embodiment, the
composite insulating system comprises an insulating component, a
safing component and a fire barrier component comprising a flexible
composite material having a first and second portion, wherein the
second portion has at least one curved portion which provides
slack, thus allowing the fire barrier to effectively lengthen and
shorten during relative movement of the building structure.
Landin et al., U.S. Pat. No. 5,765,332, discloses a fire barrier
protected dynamic joint comprising a flexible sheet of fire barrier
material and an adhesive for bonding the sheet to an attachment
area of the joint. The weight of the flexible sheet of fire barrier
material causes the middle region of said flexible sheet to sag
within the expansion joint, providing slack for the outward
expansion of the joint.
Although the above mentioned prior art fire barriers are designed
to allow for relative expansion and movement of the building
structure, none disclose the fire barrier and system of the present
invention. Thus, there is a great need in the art of fire
resistance and thermal insulation to provide a fire resistant
barrier system for building expansion joints which provides
adequate fire resistance under static and dynamic conditions, and
which retains resiliency during normal and seismic building cycling
and movement.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a
fire resistant barrier and system for dynamic expansion joints.
It is another object of the present invention to provide a fire
resistant barrier and system for dynamic expansion joints in which
the layers of the fire resistant barrier permit horizontal cyclical
movement during mechanical cycling of a building structure.
It is another object of the present invention to provide a fire
resistant barrier and system for dynamic expansion joints that
provides effective thermal insulation performance.
It is another object of the present invention to provide a fire
resistant barrier and system for dynamic expansion joints that
retains resiliency in response to normal and seismic building
cycling and movement.
These and other objects of the present invention are accomplished
by the fire barrier and method of installation which is hereafter
described and claimed. The objects and advantages of the invention
may be realized and attained by means of the embodiments and
combinations particularly pointed out in the attached claims.
The present invention, therefore, provides a fire resistant barrier
for dynamic building expansion joints comprising a plurality of
layers of fire resistant material comprising: a first mechanical
support layer having a first and second major surface; a second
layer having a first and second major surface, wherein said second
layer provides protection and mechanical support to said fire
barrier; and at least one layer of intumescent sheet material
having a first and second major surface; said at least one layer of
intumescent material is disposed between said first mechanical
support layer and said second layer; and wherein said plurality of
layers of fire resistant material comprising said fire resistant
barrier are locally bonded together over only a portion of their
width substantially continuously along the length of said
layers.
The present invention further provides a fire resistant barrier
system comprising a fire resistant barrier and at least one
radiation heat shield, said fire resistant barrier comprises a
plurality of layers of fire resistant material comprising: a first
mechanical support layer having a first and second major surface; a
second layer having a first and second major surface, wherein said
second layer provides protection and mechanical support to said
fire barrier; and at least one layer of intumescent sheet material
having a first and second major surface; said at least one layer of
intumescent material is disposed between said first mechanical
support layer and said second layer; and wherein said plurality of
layers of fire resistant material comprising said fire resistant
barrier are locally bonded together over only a portion of their
width substantially continuously along the length of said layers;
wherein said at least one radiation shield comprises at plurality
of layers of fire resistant material comprising at least one layer
of inorganic fibrous mat material having a first and second major
surface encapsulated by two layers of metalized, inorganic fiber
reinforced polymeric material; and wherein said radiation heat
shield is adapted to be installed in the space above said fire
resistant barrier, within a dynamic building expansion joint.
The present invention further provides a method of installing the
fire resistant barrier to a building structure comprising providing
a fire resistant barrier having a plurality of layers of fire
resistant material comprising: a first mechanical support layer
having a first and second major surface; a second layer having a
first and second major surface, wherein said second layer provides
protection and mechanical support to said fire barrier; and at
least one layer of intumescent sheet material having a first and
second major surface; said at least one layer of intumescent
material is disposed between said first mechanical support layer
and said second layer; and wherein said plurality of layers of fire
resistant material comprising said fire resistant barrier are
locally bonded together over only a portion of their width
substantially continuously along the length of the fire resistant
material layers; and attaching the fire resistant barrier to a
building member with retainer angle brackets.
In another embodiment of the present invention, the fire barrier
system further comprises an expansion joint cover plate to provide
a bridge across the expansion joint and to provide added fire
resistance.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of the fire barrier system
embodiment of the present invention comprising a fire barrier and a
plurality of radiation heat shields.
DETAILED DESCRIPTION OF THE INVENTION
To overcome the disadvantages of the fire resistant barriers for
expansion joints disclosed in the prior art, the present invention
provides a fire resistant barrier and system for building expansion
joints, which provides fire resistance and maintains its resiliency
during both normal and seismic building cycling or movement.
With reference to FIG. 1, the present invention provides a fire
resistant barrier 10 for dynamic building expansion joints
comprising a plurality of layers 11-13 of fire resistant material
comprising a first mechanical support layer 11 having a first and
second major surface; a second layer 13; and at least one layer of
intumescent sheet material 12 having a first and second major
surface. The layer of intumescent sheet material 12 is disposed
between said first mechanical support 11 and said second layer 13.
The second layer 13 provides protection and mechanical support to
the fire barrier and may be comprised of a polymeric material, a
fiber reinforced polymeric material, a metalized, fiber reinforced
polymeric material or a metalized, fiberglass cloth. A metalized,
fiber reinforced polymeric material, such as aluminized, glass
fiber reinforced polypropylene is the preferred material for the
second layer of the fire barrier. According to the present
invention, the plurality of layers of fire resistant material
comprising said fire resistant barrier are locally bonded together
over only a narrow portion of their width substantially
continuously along the entire length of their surfaces.
The plurality of layers of fire resistant material 11-13 are,
therefore, bonded together in a manner that allow horizontal
cyclical movement during normal and seismic mechanical cycling of
the building, without producing internal stress within the
plurality of layers of fire resistant material which could result
in the breakage of the bond between the layers. Suitable methods
for bonding the plurality of fire resistant layers together include
stitching, stapling, tacking, riveting and using an adhesive
material. The most preferred method for bonding the plurality of
fire resistant layers together is the use of an adhesive
material.
Although FIG. 1 shows the layers of the fire barrier against
substantially the entire portion of their surfaces, the layers are
locally bonded together over only a narrow portion of their width
substantially continuously along entire length of their surfaces.
This construction permits the layers of fire resistant material to
shift relative to each other without breaking, tearing or failure
of the fire barrier when exposed to thermal cycling or physical
movement or sway of the building structure.
The bonding of the plurality of layers of fire resistant material
is accomplished by using a narrow layer of adhesive between each
layer of fire resistant material. Preferably, the bonding of the
plurality of layers of fire resistant material is accomplished by
using a narrow layer of adhesive between along the longitudinal
center between each layer only. The narrow adhesive bond keeps all
the fire resistant material layers bonded together and permits
horizontal and cyclical movement of the layers in response to
normal and seismic building movement or thermal cycling.
As described above, the fire barrier of the present invention
comprises a flexible mechanical support layer. The flexible
mechanical support layer provides the primary structural and
mechanical support for the entire mass of the fire barrier of the
present invention. Suitable materials that may comprise the
flexible mechanical support layer include, but are not limited to
stainless steel, aluminum, copper, and high temperature resistant
woven textiles. The preferred material comprising the flexible
mechanical support layer is a layer of stainless steel. Examples of
high temperature resistant woven textiles include high silica
cloth, or woven ceramic fibers, sold by Unifrax Corporation under
the tradename FIBERFRAX.
The mechanical support layer may be a structure in the form of a
sheet, foil, mesh, screen or high temperature resistant woven
textile. Preferably, the mechanical support layer is provided in
the form of a metal foil, such as stainless steel foil.
The second layer of the fire barrier of the present invention
comprises a layer of material that provides protection and
mechanical or structural support to the fire barrier. The second
layer may comprise a polymeric material, a fiber reinforced
polymeric material or a metalized, fiber reinforced polymeric
material. Suitable polymers that may comprise the polymeric
material of the second layer of the fire barrier include, but are
not limited to polypropylene, polyethylene, polyester thermoplastic
elastomers and thermoplastic rubbers. The preferred polymer
comprising polymeric material comprising this layer is
polypropylene. The preferred material comprising the second layer
of the fire barrier is a metalized, fiber reinforced polymeric
material, such as aluminized, glass fiber reinforced polypropylene.
In an alternative configuration, the layer of metalized, fiber
reinforced polymeric material may be substituted with metalized
fiberglass cloth, such as aluminized fiberglass cloth.
Suitable materials that may be included in the metalized, fiber
reinforced polymeric material layer include, but are not limited to
inorganic fibers, such as glass, silica, ceramic fibers, polymeric
fibers, such as aramid fibers, and metal wire. The ceramic fibers
are preferably in the form of continuous ceramic filaments. The
preferred fibers that may comprise the metalized, fiber reinforced
polymeric material layer are glass fibers. The preferred aramid
fibers are Kevlar.TM. fibers. The metal wire may be selected from
the group consisting of steel and aluminum wire.
The metalized, fiber reinforced polymeric material layer may be
provided in the form of a sheet, paper, felt, fabric, blanket, film
or foil. The metalized, inorganic fiber reinforced polymeric
material layer is preferably in the form of a foil.
The intumescent sheet material used in the fire resistant barrier
10 may comprise an intumescent material mat paper, sheet, felt or
blanket
produced from unexpanded vermiculite, hydrobiotite, or
water-swelling tetrasilicic flourine mica using organic or
inorganic binders to provide a desirable degree of strength. The
sheet material can be produced by standard paper-making techniques
as described, for example, in U.S. Pat. No. 3,458,329, the
disclosure of which is incorporated by reference. Examples of
suitable intumescent sheet materials are disclosed in U. S. Pat.
Nos. 3,916,057 and 4,305,992, the disclosures of which are
incorporated by reference.
Alternatively, the intumescent material may comprise a mixture of
unexpanded vermiculite and expandable graphite in a relative amount
of about 9:1 to about 1:2 vermiculite:graphite, as described in
U.S. Pat. No. 5,384,188, the disclosure of which is incorporated by
reference.
Preferably, the intumescent material comprises a composite blend of
fibers, wherein the fibers are selected from refractory ceramic
fibers and high temperature resistant glass fibers, unexpanded
vermiculite, and an organic binder system. Such a material,
including Fiberfrax.TM. alumina-silica ceramic fibers, is available
from Unifrax Corporation (Niagara Falls, NY) under the XFP
Expanding Fyre Paper trademark. The high temperature resistant
ceramic fibers in the intumescent mat allow the fire resistant
barrier to withstand temperatures up to 2300.degree. F. A
representative formulation for such a preferred intumescent fire
barrier material includes about 30 to about 45 weight percent high
temperature resistant fibers (preferably alumina-silica), about 45
to about 60 weight percent unexpanded vermiculite, and about 5 to
about 10 weight percent organic binder.
The intumescent material layer of the fire resistant barrier of the
present invention expands up to three times its thickness when
exposed to temperatures above 620.degree. F. Under the conditions
of a fire, the intumescent material expands to fill joints and
voids to prevent the spread of flames, heat and smoke through the
barrier-joint edge area, to other parts of the building
structure.
The adhesive which is applied to the plurality of fire resistant
material comprising the fire resistant barrier of the present
invention may comprise a pressure sensitive rubber based adhesive,
double coated films, or a variety of rubber based hot melt
adhesives. The adhesive may be applied to the plurality of fire
resistant layers during manufacturing or during installation. When
the adhesive is applied during manufacturing of the fire barrier, a
release layer may be employed to protect the adhesive. The release
layer may be carried on a film, including paper, or a themoplastic
or thermoset polymeric film.
In another embodiment, the present invention provides a fire
resistant barrier system comprising a fire resistant barrier 10 and
at least one thin radiation heat shield 20. The fire resistant
barrier 10 includes a plurality of layers of fire resistant
material 11-13 comprising a first mechanical support layer 11
having a first and second major surface; a second layer 13 having a
first and second major surface, wherein said second layer provides
protection and mechanical support to said fire barrier; and at
least one layer of intumescent sheet material 12 having a first and
second major surface. The layer of intumescent sheet material 12 is
disposed between the first mechanical support layer 11 and the
second layer 13. The first mechanical support layer 11, the second
layer 13 and at least one layer of intumescent sheet material 12
comprising the fire resistant barrier 10 are locally bonded
together over only a portion of their width substantially
continuously along the length of said layers of fire resistant
material, preferably with a narrow layer of adhesive material along
the longitudinal center. The plurality of fire resistant material
layers may also be bonded together using tape, tacks, staples or
rivets.
The radiation heat shields 20 preferably comprises a plurality of
layers of fire resistant material 21-23 comprising at least one
layer of inorganic fibrous mat material 22 having a first and
second major surface encapsulated by two layers of metalized,
inorganic fiber reinforced polymeric material 21, 23. The radiation
heat shields 20 are adapted to be installed in the space above the
fire resistant barrier, within a dynamic building expansion joint.
The thickness of each of the layers of fire resistant material
comprising the radiation heat shield is about 1/16 to about 1/2
inches, but may vary depending on the specific application
conditions.
In the fire resistant barrier assembly described hereinabove, the
radiation shield preferably contains an inorganic fibrous mat
material or paper layer. The inorganic fibrous mat material or
paper layer may comprise alumina-silica glassy fiber and shot,
together with an organic binder. A preferred alumina-silica ceramic
fiber paper having a 70/30 fiber/shot ratio and containing about 7
weight percent organic binder is available under the tradename
Fiberfrax.TM. paper from Unifrax Corporation (Niagara Falls, N.Y.),
as well as a higher temperature resistant ceramic fiber paper
produced from Fibermax.TM. polycrystalline mullite ceramic fibers.
Other suitable refractory papers useful in the present invention
comprise heat resistant Insulfrax.TM. and Isofrax.TM. glass fibers,
also available from Unifrax Corporation, or fiberglass, such as E
glass and S2 glass.
The present invention further provides a method of installing the
fire resistant barrier 10 to building structure members 40, 42
comprising providing a fire resistant barrier 10 having a plurality
of layers of fire resistant material 11-13 comprising a first
mechanical support layer 11 having a first and second major
surface; a second layer 13 having a first and second major surface,
wherein said second layer provides protection and mechanical
support to said fire barrier; and at least one layer of intumescent
sheet material 12 having a first and second major surface. As
described above, the layer of intumescent sheet material 12 is
disposed between said mechanical support layer 11 and the second
layer 13. The first mechanical support layer 11, the second layer
13 and the layer of intumescent sheet material 12 comprising said
fire resistant barrier 10 are locally bonded together over only a
portion of their width substantially continuously along the entire
length of their surfaces. The method further includes attaching the
fire resistant barrier 10 to building members 40, 42 with retainer
angle brackets 30, 32.
The thermal performance of the fire barrier of the present
invention increases as the length of the retainer angle brackets is
increased. Thermal performance is improved by increasing the length
of the retainer angles up to the thickness of the concrete
structure to which it is attached. When the fire barrier is
installed in a building expansion joint it is important that the
layers of fire resistant material are held tight against the
surface of the concrete building members to provide a tight seal
between the building member and the fire barrier system, thus
preventing the transfer of fire, smoke and hot gas from the area
below the fire barrier to the area above the fire barrier system. A
tight seal between the fire barrier and the concrete building
member is enhanced by anchoring the fire barrier to the concrete
building members with angular brackets having an angle bend of
about 85 degrees and a leg length that is substantially equal to
the thickness of the concrete building member. The design of the
fire barrier of the present invention does not require the use of
conventional caulking materials to form a tight seal between the
fire barrier and the concrete building members.
The fire resistant barrier material layers are not pulled tautly,
but contain slack to allow for movement perpendicular to the
lengthwise direction of the joints. The fire barrier is preferably
mechanically affixed to the structural members. The mechanical
attachment may be by means of galvanized angle irons 30, 32 bolted
to the building members 40, 42 to form a permanent, immovable
attachment, such as with masonry anchors 34, 36, or in some
instances, may provide for horizontal cyclical movement within the
expansion joint.
In another embodiment of the present invention, the fire barrier
may further comprise a expansion joint cover plate to provide a
bridge across the expansion joint and to provide additional fire
resistance. The materials that may comprise the expansion joint
cover plate are selected from the group consisting of galvanized
steel, magnesium, stainless steel, bronze, brass and aluminum. The
preferred material useful in the present invention is aluminum. The
cover plate may be attached to a concrete building structure
members by any suitable means such as masonry anchors, screws and
power anchors. The cover plate is preferably attached to the
concrete building structure members with masonry anchors.
Because of the design of the fire barrier of the present invention,
having the layers of fire resistant material locally bonded over
only a portion of the width of their surfaces, the fire barrier of
the present invention is capable of a horizontal cyclical movement
in the range of about .+-.50-90 percent of the nominal joint
opening size. The fire resistant barrier of the present invention
therefore accommodates the normal and seismic cycling movement of
architectural structures, unlike the fire barriers of the prior
art.
GENERAL EXPERIMENTAL
The fire resistance and integrity of the fire resistant barrier of
the present invention were evaluated by tests defined by
Underwriter's Laboratories Test for Fire Resistance of Building
Joint Systems (UL Test Number 2079). Prior to fire testing, the
fire barrier was subjected to a minimum of five hundred complete
movement cycles to provide a condition representative of expansion
joints in building structures.
The fire barrier of the present invention passes both the seismic
cycling and fire test criteria of UL Test Number 2079-Test for Fire
Resistance of Building Joint Systems. The fire resistant barrier of
the present invention provides extreme horizontal cyclical movement
and maintains its structural integrity during the normal cycling
and movement of building structures. The fire resistant barrier of
the present invention is optimized to reduce cost and weight, while
still passing both the cycling and fire resistance requirements of
UL test number 2079.
The fire resistant barrier of the present invention can be designed
in a variety of sizes, each appropriate for a specific joint design
or size. The design of the fire resistant barrier of the present
invention is optimized for expansion joint having nominal openings
ranging from 1 inch to 6 inches. The fire barrier and system of the
present invention may be adapted for floor, wall, ceiling, corner
wall, floor to wall, floor to corner wall, wall to ceiling and
corner wall to ceiling applications. The fire barrier of the
present invention may be provided in a roll which allows for
greater flexibility of installation and reduces the number of
splice joints required.
It is thus demonstrated that the fire resistant barrier of the
present invention achieves the objects of the invention. The
objects of the invention are accomplished by the fire resistant
barrier and method of installation of the present invention, which
is not limited to the specific embodiments described above, but
which includes variations modifications and equivalent embodiments
defined by the following claims.
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